Alcidodes toyi Lyal, 2000

Lyal, C. H. C. & Curran, L. M., 2000, Seed-feeding beetles of the weevil tribe Mecysolobini (Insecta: Coleoptera: Curculionidae) developing in seeds of trees in the Dipterocarpaceae, Journal of Natural History 34 (9), pp. 1743-1847 : 1799-1800

Alcidodes toyi Lyal , n.sp.

Length 6.6±11.1 mm (xÅ5 l9.22, m 9.87), PW5 2.9±4.6 mm (xÅ5 l4.05, m 4.33), HW5 3.4±6.25 mm (xÅ5 l5.16, m 5.58) (n 5 l30, m 25) (®gures 26, 58, 75).

Head. Rostrum weakly curved, slightly longer and more slender in female (RL 5 4.63±6.63 mm, xÅ5 5.69, RL/PW 5 1.21±1.38, xÅ5 1.31; RB/RD 5 0.54±0.71, xÅ5 0.63; n 5 25) (®gure 193) than in male (RL 5 3.13±5.00, xÅ5 4.21 mm; RL/PW 5 0.90±1.27, xÅ5 1.04; RB/RD 5 0.65±0.89, xÅ5 0.78; n 5 30) (®gure 194).

Thorax. PL/PW, m, 0.74±0.81 (xÅ5 0.78, n 5 26),, l0.66±0.81 (xÅ5 0.74, n 5 30); prothorax sometimes swollen behind fore coxae but lacking a tubercle in that position. Elytra with interstriae smooth or weakly wrinkled proximally, strial punctures deep, as wide or narrower than interstriae, humeri with interstria 9 not, or only weakly, projecting beyond 8 in dorsal view (®gure 26); EL/HW, m, 1.16±1.32 (xÅ5 1.25, n 5 26),, l1.21±1.44 (xÅ5 1.27, n 5 30). Elytra with darker pigmentation on humeri and on posterior parts of interstriae 4±6; elytral scales broadest and more dense along all margins. Fore femur with ventral tooth subtriangular, lacking proximal lobe, proximal margin at c.90ss to the long axis of the femur and at least as high as the length of the tooth with proximal and distal margins meeting femur at approximatel y the same level, the distal margin dentate or serrate and with relatively steep slope (®gures 133, 156, 157); all tibiae with (sometimes small) ventral tooth. Metasternum strongly produced posteroventrally before hind coxae, its ventral margin strongly diverging from elytral margin.

Abdomen. Ventrite 5 with two caudal setal tufts on prominences on raised posterior margin in both sexes, those of male larger than those of female; disc depressed medially (®gures 100, 101).

Male terminalia. Tergite 7 as in ®gure 280; short submarginal row of plectral tubercles on each side. Segment 8 as ®gure 281. Genitalia as in ®gures 282±287. Tegmen with parameres fused at base (®gure 283). Aedeagus with apex rounded, downturned, sides rounded basally, weakly concave and converging towards apex, sclerotization extending only slightly onto dorsal surface (®gure 285), distance from ostium to apex much less than width of ostium (®gure 286); ostiolar sclerites not fused to aedeagal body.

Female terminalia. (®gures 288±290) Tergite 7 with small row of plectral tubercles on either side of midline (®gure 288). Tergite 8 with rounded posterior margin, disc and median anterior margin very weakly sclerotized (®gure 289). Spiculum ventrale (®gure 290) with broad part not at sharp angle to apodeme. Female genitalia as in ®gures 291±292; hemisternites shorter than broad part of spiculum ventrale, styli not enlarged and ¯attened (®gures 291±292); spermathecal duct arising at junction between bursa and oviduct; spermatheca with ¯exed tubular gland lobe (®gure 291).

Distinguishing features. A. toyi is one of the larger species of the crassus subgroup with a steep distal margin to the fore femoral tooth, being of similar size to humeralis (from which it can be easily distinguished by its much less produced humeral angles) (®gures 26, 58, cf. ®gures 33, 65), and larger and more elongate than the three species feeding on Hopea , namely walliorum , confusus and fugitus . The last three species also have their humeral angles more pronounced than those of A. toyi (®gures 27±29).

Comments. The specimens from Peninsular Malaysia are on average larger than those from the same host (Dryobalanop s aromatica ) from Borneo. A. toyi is the only species in Alcidodes so far known to feed on the seeds of Dryobalanops spp. and records of Alcidodes crassus from D. oblongifolia Dyer and D. aromatica in Daljeet- Singh (1974) probably refer to A. toyi . Momose et al. (1994) note that seeds of Dryobalanop s lanceolata in Sarawak are fed on by larval `Mecysolobus crassus ’; these specimens have been seen and are A. toyi . Records in Toy (1988) of Alcidodes spp from Dryobalanop s aromatics refer to A. toyi .

Etymology. The species is named for Robin Toy, who ®rst collected long series of Alcidodes reared from dipterocarp seeds.

Specimens examined

HOLOTYPE, l Malaysia: Peninsular Malaysia, with labels:`Holo-/ type’ and` MALAYSIA / Selangor / FRIM, Kepong / 6 August 1985.#37’ and`37/9’ and`Reared from seed / of Dryobalanops / aromatica ’ and` R.Toy Coll / B.M.1992±170’ and` HOLOTYPE / Alcidodes toyi / Lyal’ and`132’ ( BMNH).

PARATYPES: Malaysia: Peninsular Malaysia : 3 ll, 6mm, same data as holotype ( BMNH) ; 3 ll, 3mm, same locality and host ( Intachat ), pupated 25 June 1991, emerged 1.vii.1991 ( FRIM) ; 1, l same locality and host, 19 February 1916 (Holman Hunt) ( BMNH) ; 1, l same locality and host, 30 March 1955 ( BMNH) ; 2 ll, Kuala Lumpur 12, 14 September 1916 ( BMNH) ; 1, l Kapur , 7 February 1929 ( BMNH) .` MALAYA’: 1, l 22 July 1965 ( Ozaki ) ( USNM) .

Malaysia: Borneo: Sabah, 18 ll, 15mm, Sandakan, VIII-IX.1976, reared from seeds of Dryobalanop s aromatic a, ( R. Smith) ( BMNH); 1, l 2mm, Sabah: Bidu-Bidu, Beluran, vii.1990, reared from seeds of Dryobalanop s keithii, (Lantoh) (FRCS) ; 2 ll, 1m, same locality and collector, reared from seeds of Dryobalanop s beccarii (FRCS) .

Brunei: 3 ll, 2mm, Temburong Distr., Kuala Belalong (Lyal and Margerison Knight), reared from seeds of Dryobalanop s lanceolata (RMB, BMNH) .

Other material. Malaysia: Borneo: Sarawak, 31 ll, 47mm, Miri, Lanbir Hills National Park , 18 July 1993 (Nagamitsu), reared from seeds of Dryobalanops lanceolata (CERK, BMNH) .

Range. Peninsular Malaysia, Borneo.

Hosts. Dryobalanop s aromatica Gaertn. , D. lanceolata Burck , D. keithii Sym. , D. beccarii Dyer. and probably D. oblongifolia Dyer.